Aircraft powerplant

ABSTRACT

A gas turbine engine system is disclosed which includes a core passage and a bypass passage which can be configured as a fan bypass duct or a third stream bypass duct. The core passage and bypass passage are routed to flow through a nozzle before exiting overboard an aircraft. The nozzle includes moveable members capable of changing a configuration of the nozzle. In one form the moveable members are capable of changing throat areas for portions of the nozzle that receive working fluid from the core passage and the bypass passage. The bypass passage can include a branch. In one form the branch can include a heat exchanger. The bypass passage can also provide cooling to one or more portions of the nozzle, such as cooling to a deck of the nozzle.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of U.S. Provisional PatentApplication No. 61/496,876 filed Jun. 14, 2011, which is incorporatedherein by reference.

TECHNICAL FIELD

The present invention generally relates to aircraft powerplants, andmore particularly, but not exclusively, to aircraft nozzles.

BACKGROUND

Providing flow path configurations for aircraft powerplants capable ofoperating over a range of conditions remains an area of interest. Someexisting systems have various shortcomings relative to certainapplications. Accordingly, there remains a need for furthercontributions in this area of technology.

SUMMARY

One embodiment of the present invention is a unique aircraft powerplantsystem. Other embodiments include apparatuses, systems, devices,hardware, methods, and combinations for flowing working fluid within anaircraft powerplant. Further embodiments, forms, features, aspects,benefits, and advantages of the present application shall becomeapparent from the description and figures provided herewith.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 depicts an embodiment of an aircraft and gas turbine engine.

FIG. 2 a depicts an embodiment of a bypass passage.

FIG. 2 b depicts an embodiment of a bypass passage.

FIG. 2 c depicts an embodiment of a bypass passage.

FIG. 3 a depicts an embodiment of a nozzle.

FIG. 3 b depicts an embodiment of a nozzle.

FIG. 3 c depicts an embodiment of a nozzle.

FIG. 4 depicts an embodiment of a nozzle.

FIG. 5 a depicts an embodiment of a nozzle member.

FIG. 5 b depicts an embodiment of a nozzle member.

FIG. 6 a depicts an embodiment of cross sectional variation of a nozzlemember.

FIG. 6 b depicts an embodiment of cross sectional variation of a nozzlemember.

FIG. 7 depicts an embodiment of a nozzle and nozzle member.

FIG. 8 depicts an embodiment of various passages.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended. Any alterations and further modificationsin the described embodiments, and any further applications of theprinciples of the invention as described herein are contemplated aswould normally occur to one skilled in the art to which the inventionrelates.

With reference to FIG. 1, there is illustrated a schematicrepresentation of one form of a gas turbine engine 50 used as apowerplant for an aircraft 51. As used herein, the term “aircraft”includes, but is not limited to, airplanes, unmanned space vehicles,fixed wing vehicles, variable wing vehicles, unmanned combat aerialvehicles, tailless aircraft, and other airborne and/or extraterrestrial(spacecraft) vehicles. The gas turbine engine 50 includes a fan 52,compressor 54, combustor 56, and turbine 58. In one form of operation, aworking fluid 60 such as air entering the gas turbine engine 50 isaccelerated by the fan 52. Some of the working fluid enters a corepassage 62 of the core engine which includes a passage through thecompressor 54, combustor 56, and turbine 58. Working fluid that does notpass through the core passage 62 bypasses the core engine and flows in afan bypass duct 64. After passing through the core engine an exhaustflow is discharged through a nozzle 66. In some forms the working fluidpassing through the fan bypass duct 64 is combined with the exhaust flowprior to being discharged through the nozzle 66, but in other forms theworking fluid passing through the fan bypass duct 64 can exit elsewhere.

The gas turbine engine 50 also includes a third stream bypass duct 68capable of flowing a working fluid conveyed via a turbomachinerycomponent powered by operation of the gas turbine engine 50. In one formthe third stream bypass duct 68 is operable to withdraw a portion ofworking fluid traversing through the gas turbine engine 50, such as butnot limited to through the fan bypass duct 64. In some embodiments thethird stream bypass duct 68 can withdraw a portion of the working fluidat a location downstream of a fan that provides working fluid to the fanbypass duct 64. In yet another form the third stream bypass duct 68 canhave its own turbomachinery component such as but not limited to a bladeportion separated from and disposed radially outward of a fan bypassportion of a bladed turbomachinery component. The third stream bypassduct 68 is operable to convey a quantity of working fluid 60 to providean additional thrust capability to the propulsion system and/or toprovide an additional stream of pressurized air for use as a coolant orenergy source. The relatively low temperature of the working fluidthough the third stream bypass duct 68 can provide a thermal managementheat sink and could allow use of relatively economical materials inexhaust ducting and liners. In one form the third stream bypass duct 68can convey a quantity of working fluid 60 to be used as an additionalenergy source to provide power for electrical or mechanical devices. Aflow of working fluid through the third stream bypass duct 68 can becombined with working fluid flowing through either or both of the fanbypass duct 64 and core passage 62 to flow through the nozzle 66, butsome embodiments can include the working fluid through the third streambypass duct 68 as exiting independent of any given nozzle that conveysone or more flows.

In one non-limiting embodiment the third stream bypass duct 68 canwithdraw working fluid 60 from the fan bypass duct 64 at a locationdownstream of the fan 52. In this configuration the gas turbine engine50 includes the core passage 62, fan bypass duct 64, and third streambypass duct 68, all of which are capable of flowing some portion of aworking fluid received through an inlet to the gas turbine engine 50. Insome embodiments the third stream bypass duct 68 can flow a quantity ofworking fluid approaching that amount carried through the fan bypassduct 64. The third stream bypass duct 68 can withdraw working fluid 60from the fan bypass duct 64 at locations other than those discussedabove. To set forth just one non-limiting example, the third streambypass duct 68 can withdraw working fluid at a location between fanstages.

The working fluid 60 withdrawn through the third stream bypass duct 68can be recombined with an exhaust flow of the gas turbine engine 50prior to being discharged to ambient conditions. For example, theworking fluid that flows through the third stream bypass duct 68 can berecombined in the nozzle 66 with a working fluid that flowed through thecore passage 62 and the fan bypass duct 64. Various embodiments of thenozzle 66 capable of combining flow from any of the core passage 62, fanbypass duct 64, and third stream bypass duct 68 will be describedfurther below.

The gas turbine engine 50 can take any variety of forms. For example,the gas turbine engine 50 can have any number of spools capable ofdriving any number of compressor 54 and turbine 58 sections. In someforms the gas turbine engine 50 can be an adaptive cycle, variablecycle, combined cycle engine and can be used at a variety of flightconditions. As such, the aircraft 51 typically includes a sensor 70 andcontroller 72 for determining flight condition and operating one or moresystems aboard the aircraft, such as but not limited to the gas turbineengine 50.

The sensor 70 can typically be used to measure aircraft flight conditionsuch as speed and altitude, to set forth just two non-limiting examples,and can output any variety of data whether sensed or calculated. Forexample, the sensor 70 can sense and output conditions such as statictemperature, static pressure, total temperature, and/or total pressure,among possible others. In addition, the flight condition sensor 70 canoutput calculated values such as, but not limited to, equivalentairspeed, altitude, and Mach number. Any number of other sensedconditions or calculated values can also be output. The flight conditionsensor 70 provides data to the controller 72 and can output values ineither analog or digital form.

The controller 72 is provided to monitor and control engine operations.The controller 72 can be comprised of digital circuitry, analogcircuitry, or a hybrid combination of both of these types. Also, thecontroller 72 can be programmable, an integrated state machine, or ahybrid combination thereof. The controller 72 can include one or moreArithmetic Logic Units (ALUs), Central Processing Units (CPUs),memories, limiters, conditioners, filters, format converters, or thelike which are not shown to preserve clarity. In one form, thecontroller 72 is of a programmable variety that executes algorithms andprocesses data in accordance with operating logic that is defined byprogramming instructions (such as software or firmware). Alternativelyor additionally, operating logic for the controller 72 can be at leastpartially defined by hardwired logic or other hardware. In oneparticular form, the controller 72 is configured to operate as a FullAuthority Digital Engine Control (FADEC); however, in other embodimentsit may be organized/configured in a different manner as would occur tothose skilled in the art. It should be appreciated that controller 72can be exclusively dedicated control of the gas turbine engine 50, ormay further be used in the regulation/control/activation of one or moreother subsystems or aspects of aircraft 51, such as but not limited tothe nozzle 66.

Turning now to FIGS. 2 a, 2 b, and 2 c one embodiment of a bypasspassage 74 capable of providing a flow of working fluid to the nozzle 66is depicted in which the bypass passage 74 is in an annular form at anupstream station 75 of the gas turbine engine 50 (shown in FIG. 2 c),but is split to form a passage displaced to one side of the gas turbineengine 50 and partially extending around the periphery of the engine 50at a downstream station. FIG. 2 a depicts a top view of the bypasspassage 74, and FIG. 2 b depicts a side view. The bypass passage 74 isshown in the illustrated embodiment as being ducted to a displacedposition on a lower side of the gas turbine engine 50 in an underslungconfiguration, but other configurations are also contemplated herein.The terms “top”, “front”, “side”, “lower” and other relational words areused herein for ease of reference only and are not otherwise limiting toany particular embodiment. The bypass passage 74 extends between anupstream side 75 to a downstream side 77. The dashed line indicated byreference numeral 50 indicates an outer casing of one embodiment of thegas turbine engine 50 such that the bypass passage 74 at least in partencloses the engine 50.

The bypass passage 74 can be the third stream bypass duct 68 asdescribed above. The bypass passage 74 can further include a splitter 76useful to divide a working fluid within the bypass passage 74. In oneform the splitter 76 can be configured to route a portion of the workingfluid in the bypass passage 74 to flow within a branch 78 as shown inFIG. 2 b. As will be appreciated, a flow of working fluid through thebranch 78 can be combined with a flow of working fluid through any oneor more of the core passage 62, fan bypass duct 64, and third streambypass duct 68 to flow through the nozzle 66, but some embodiments caninclude the working fluid through the branch 78 as exiting independentof any given nozzle that combines any two or more flows. Any number ofsplitters 76 can be used in various embodiments to form any number ofbranches 78. The splitter 76 can take any variety of arrangements usefulto split flows between the bypass passage 74 and the branch 78. Anynumber of splitters can be used to form any number of branches. In someembodiments, a splitter 76 can be used to form branches 78 on eitherside of the gas turbine engine. The splitter 76 can divide fluidcircumferentially as shown, but other variations of splitting flow arealso contemplated herein.

The branch 78 can be routed to various portions of the gas turbineengine 50 and can deliver working fluid to, among other possiblelocations, the nozzle 66. As will also be understood given thedescription herein, the branch 78 can also be routed to various portionsof the aircraft 51. The illustrated embodiment includes a pair ofbranches 78 disposed opposite one another, but other embodiments caninclude any variety of configurations.

In one non-limiting embodiment a device that would benefit from flowrate flexibility and control provided by the embodiments herein can beused with one or more of the branches. For example, a device configuredto thermodynamically interact with, and in some forms operate upon, theworking fluid can be coupled with one or both branches 78. In one formthe device can be disposed in a branch 78 but other locations are alsocontemplated in which the device interacts with working fluid conveyedthrough one or more branches 78. In one non-limiting example, the devicecan be a heat exchanger that can be used to cool a relatively hightemperature component associated with the gas turbine engine 50 and/orthe aircraft 51 using the working fluid traversing through the branch78. Such a heat exchanger can be a solid state variety, a heat exchangerincluding a fluid that flows through the heat exchanger, a fluid thatflows in a closed circuit within the heat exchanger, a phase change heatexchanger, etc, to set forth just a few non-limiting embodiments. Anygiven heat exchanger can be located anywhere within the branch 78. Toset forth just a few non-limiting examples of how the heat exchanger isdisposed in the branch 78 and interacts with working fluid in the branch78, the working fluid can flow through, around, over, etc, or acombination thereof, of the heat exchanger. The heat exchanger, and forthat matter any device that would benefit from being coupled with thebranch 78, can be located anywhere with the branch 78 such as at thebeginning of the branch 78, the end of the branch, or any intermediateposition. In some forms the device can be used to form part of thepassage whether at the beginning, end, or anywhere in between. In someforms a heat conducting plate or other device can be interposed betweenthe working fluid and the heat exchanger. Multiple heat exchangers canbe used in various embodiments. To set forth just one non-limitingexample, in those embodiments having more than one branch 78, eachbranch 78 can have at least one heat exchanger.

The branches 78 can be configured to provide a relatively constant flowof working fluid to provide cooling to the heat exchanger and can do soin some embodiments even with changes in engine power settings. Forexample, where the bypass passage 74 takes the form of the third streambypass duct 68, the branch 78 can be configured to provide consistentflow rates therethrough while larger variations are experienced in thebypass passage 74 as a result of engine operations. In some non-limitingforms the branch 78 can have a constant flow rate during many and/or allmodes of engine operation which include a range of engine conditions,while in other non-limiting forms the branch 78 can have some amount offluctuation in flow rate that nonetheless remains a smaller fluctuationthan the fluctuation in flow rate in the bypass passage 74 over thosesame ranges of engine conditions. In one non-limiting example, thebranch 78 can have a flow rate that remains substantially the same fromminimum to military power settings, and sometimes throughout afterburneroperation as well. Other ranges are also contemplated.

The ability to provide substantially the same flow rates can be assistedthrough use of variable geometry flow path provided in the bypasspassage 74, some embodiments of which are discussed further below.Additionally and/or alternatively, in some forms the branches can havefixed or variable geometry, as discussed further below. Thus, it ispossible to operate a variable geometry flow paths in either or both thebypass passage 74 and the branch 78 to provide for substantially thesame flow rate within the branch 78 over a range of engine operation.Various embodiments of the variable geometry flow paths are discussedfurther below, and can take the form of a pivoting mechanism,translating mechanism, fluidic mechanism, etc to set forth just a fewnon-limiting examples of the ability to change a flow area.

As will be appreciated, the variable geometry mechanisms can also beused to control flow rates to other values that can vary depending upona need of a device coupled with the branch, such as with a heatexchanger coupled with the branch. In such embodiments the variablegeometry mechanisms can control flow rates, such as a flow rate thatvaries with demand requirement of the device, either at a specificengine operating condition, or across a range of engine operatingconditions. To set forth just one more additional example, the flow ratecan be controlled in a manner that is dependent upon a desiredinteraction with the thermodynamic device. In one form the thermodynamicdevice may have a variable heat load during operation of the gas turbineengine where the heat load is required to be rejected to the workingfluid flowing through the branch 78. The variable geometry mechanisms,whether associated with one or more of the passages/branches, can becontrolled to accommodate the varying heat rejection requirements. Forexample, if a high temperature is required to be rejected the flow ratecan be adjusted via the variable geometry mechanisms, to increase flowrate and thus heat transfer. The adjustment to the variable geometrymechanism can take place within the controller 72 based upon a sensedtemperature of the heat exchanger, fluid within the heat exchanger,etc., to set forth just one possibility. The subsequent change to flowrate in the branch 78 can be satisfactory to the thermodynamic device insome embodiments even if measured temperature climbs somewhat above thetarget value consistent with operation of feedback controllers,feedforward controllers, etc. and bands of satisfactory performanceassociated with controller operation.

As will be appreciated, FIG. 8 discloses one embodiment of a device inthe form of a thermodynamic device that is in the form of a heatexchanger 120 disposed within the branch 78. Such a thermodynamic devicecan be capable of exchanging at least one of heat and work with theworking fluid flowing through the branch 78. The branch 78 includes anexit or nozzle 122 that can be fixed or variable. An exit or nozzle 124of the bypass passage 74, as well as an exit or nozzle 126 of flowpassage 84 (described below), can either or both be fixed or variable.In one form of the present application, the Mach number of the flowentering the branch 78 can be variable and a variable geometry exit 122can provide for a constant Mach number flow through the branch 78. Giventhe description it will be understood that heat rejection via heatexchanger 120 and fuel consumption influenced by the bypass passage 74can be independently controlled in some embodiments. In some forms itmay be only necessary to vary the exit or nozzle 124 while fixing theexit or nozzle 122, depending on heat rejection requirements.

The arrangement in FIG. 8 can be applicable to any bypass passage havinga branch. For example, the passage labeled as 84 in the figure canrepresent the core passage 62, the passage labeled 74 in the figure canrepresent the bypass passage 64, and the passage labeled as 78 canrepresent a branch from the bypass passage 64. Thus, the arrangementshown in FIG. 8 can be used in many different passages and not limitedto a branch from the third stream passage. For that matter, the passagelabeled 74 can be a fourth, fifth, sixth, etc stream. In this manner itwould be understood that a first passage would be akin to the corepassage, the second passage akin to a bypass passage such as a fanbypass, the third passage akin the third stream bypass passage, and soon and so forth with each subsequent stream representing a streamfurther removed from the core and/or further lower in pressure relativeto the core. To set forth just one non-limiting example of what woulddifferentiate the various streams, the second stream such as the fanbypass passage will have a lower pressure than the core stream at aposition upstream of the turbine. The third stream will have a lowerpressure still than the second stream. A fourth stream a lower pressurestill. Etc. Furthermore, though the passages 74 and 78 are showndisplaced radially from the passage 84, in some forms one or both of thepassages 74 and 78 can be annular. In one form the passage 78 will beunderstood to be a branch from passage 74 capable of conveying a workingfluid from the passage 74 after a working fluid flowing through thepassage 74 has already passed a turbomachinery component, such as a fan,and is free from subsequent turbomachinery components through theremainder of the passage 74 downstream from the split in flow to formthe passage 78.

Any of the branch 78 and passages 74, 84 are considered to be thepassageway that conveys working fluid before the fluid is consumed by alarger volume such as an external exit to ambient conditions, or to anozzle where it is combined with other flows, to set forth just twonon-limiting examples. Thus, multiple segments/conduits/passages can becoupled to form any of the branch 78 and passages 74, 78.

Arrangements as depicted in FIG. 8 will be appreciated given thediscussion herein to have numerous variations. For example, any ofreference numerals 122, 124, and 126 can represent independent exits, orcan be flowed into a nozzle that can be a common nozzle as shown in someembodiments below, or combined into one or more separate nozzles.Whether the reference numerals 122, 124, 126 represent exits or nozzlesor a combination thereof, no limitation is hereby intended of thenumerals 122, 124, 126. The exits or nozzles represented by numerals122, 124, 126 can be at locations that are separate from one anothersuch that none has an influence on the flow of the others prior to beingdischarged from the aircraft 51 or gas turbine engine 50. In still otherembodiments, any two or more of the exits or nozzles 122, 124, 126 canbe positioned such that the flows influence each other. In addition, thevariable nature of the exit or nozzles 122, 124, and 126 can, but neednot use similar variable geometry flow path mechanisms. For example, theexit or nozzle 122 can use a pivoting arrangement while the exit ornozzle 124 can use a translating arrangement. Furthermore, any or all ofthe variable geometry flow path mechanisms can be controlled by thecontroller 72. Thus, no limitation is hereby intended regarding thecombinations and arrangements of any of the flow paths, exits ornozzles, etc.

Turning now to FIGS. 3 a, 3 b, and 3 c, a side view is shown of thenozzle 66 in which a working fluid from the bypass passage 74 and aworking fluid from a flow passage 84 is received. The flow passage 84can be either or both the core passage 62 and fan bypass duct 64. To setforth just one non-limiting example, in some embodiments the flowpassage 84 can include working fluid from both the core passage and fanbypass duct 64. The working fluid flowing through the bypass passage 74can be received by the nozzle 66 from the downstream side 77 as shownabove in FIGS. 2 a and 2 b. In those embodiments having the branch 78the working fluid received by the nozzle 66 can, but need not, beseparate from working fluid in the branch 78.

The nozzle 66 includes an upper translatable member 80 capable oftranslating along the indication shown by reference numeral 86 and alower translatable member 82 capable of translating along the indicationshown by reference numeral 88, both members 80 and 82 of which arecapable of changing a configuration of the nozzle 66. As will beappreciated, either or both the members 80 and 82 can be capable oftranslating in a number of different ways, including along a straightline in some embodiments. Although the indications shown by referencenumerals 86 and 88 are not parallel, not all embodiments need bearranged as such. As will be appreciated, in some embodiments either orboth members 80 and 82 have no lateral hingelines.

The translatable member 80 includes an upstream side 90 and a downstreamside 92. The translatable member 82 includes an upstream side 94 and adownstream side 96. As shown in the figures, the downstream side 92 ofthe translatable member 80 can be configured to follow along the wall 98of the nozzle 66. The downstream side 96 of the translatable member 82can be moved such that it closes and/or substantially discouragesworking fluid from exiting the bypass passage 74 to the nozzle 66, asshown in FIGS. 3 b and 3 c.

A flow area 100 can be defined between the translatable member 80 andtranslatable member 82. In some embodiments the flow area 100 can bereferred to as A8. A flow area 102 can be defined between thetranslatable member 82 and a nozzle structure 104 which in someembodiments can be referred to as A28. The areas 100 and 102 can bechanged during operation of the gas turbine engine 50. For example, theconfiguration shown in FIG. 3 a depicts an arrangement of nozzle membersto provide for an optimum specific fuel consumption. The configurationshown in FIG. 3 b depicts an arrangement of the nozzle members toprovide for a maximum thrust mode without operation of an afterburner.The configuration shown in FIG. 3 c depicts an arrangement of the nozzlemembers to provide for a maximum thrust mode augmented with operation ofan afterburner.

The nozzle 66 also includes a surface 106 downstream of the translatablemember 82 which is used for an exhaust of the nozzle to flow along. Theexhaust is composed of either or both the working fluid from the bypasspassage 74 and working fluid from the core passage 62, or its variationsas discussed above. In some forms the surface 106 forms a deck alongwhich the exhaust flows. In one non-limiting embodiment the surface 106is included to form a single expansion ramp nozzle.

Turning now to FIG. 4, a top view of the nozzle 66 is shown. The wall 98is shown in which a downstream edge 108 includes a discontinuous shape.Though the illustrative embodiment depicts the downstream edge 108 ashaving the form of a serrated edge, in other embodiments the downstreamedge 108 can take other forms whether discontinuous or continuous.

The flow surface 106 is also depicted and is shown as including adownstream edge 110 that is continuous in shape. Other embodiments caninclude a downstream edge 110 that has other shapes. In some forms thedownstream edge 110 can mimic the downstream edge 108 of the wall 98.Either or both of the downstream edges 108 and 110 can mimic the form ofan aircraft structure. For example, the aircraft 51 can include astructure having an edge or edges that are arranged at, or substantiallyat, the same angle as one of the edges 108 depicted in the figure.

The nozzle 66 can receive a flow of working fluid from the branch 78through one of its walls. In the illustrated embodiment the workingfluid is shown exiting in proximity to the downstream edge 108. Otherconfigurations are also contemplated. The flow of working fluid exitingfrom the branch 78 can either flow through a fixed or variable areaopening. The opening can be an elongated slot or other useful opening.The slot can be arranged normal to an engine reference axis, or at anangle thereto.

The deck 106 can receive flow from either the bypass passage 74 or fromthe branch 78 to provide cooling. In one form the deck 106 can receiveflow and pass it through one or more apertures such as a slot or holes.The slot or holes can form, among other things, structural arrangementsthat provide effusion cooling. In some forms the holes and slots can besized to provide a film of cooling air to the surface 106 of the deck.In still other embodiments the flow from either the bypass passage 74and the branch 78 can provide backside convective cooling.

FIGS. 5 a and 5 b depict top profiles of the translatable members 80 and82. Upstream sides 90 and 94, as well as downstream sides 92 and 96 ofthe illustrated embodiment include edges having discontinuous shapes.The shapes follow at least part of the form of the downstream edges 108of the wall 98, but in other embodiments the shapes can take differentforms. For example, the shapes of the sides 90-96 can be continuous. Thesides can also follow contours other than the shapes of the downstreamedges 108 of the wall 98.

FIGS. 6 a and 6 b show cross sectional views of one embodiment of themember 82. The cross sectional views represent different butt linestations of the member 82. In one non-limiting example the cross sectionshown in FIG. 6 a can represent a lateral side of the member 82 whilethe cross section shown in FIG. 6 b can represent a median location,such as a center of the member 82. The variation of cross section canprovide a shape of either or both the flow areas 100 and 102 that aretailored. For example, when the flow area 100 represents a throat areaA8 of the nozzle 66 the variation in cross sectional shape of member 82can provide a shape of throat area different than the shape representedby either members 80 and 82 as shown in FIGS. 5 a and 5 b. Oneembodiment of a throat shape different than the shape of the members 80and 82 is discussed further below. Though the illustrated embodimentdepicts a variation in cross sectional shape of the member 82, in someembodiments the member 82 can additionally and/or alternatively includea variation in cross sectional shape. In some embodiments a sweptejector slot can be provided.

FIG. 7 shows a throat A8 as a result of contoured shaping of the member82. The throat A8 is shown as lying upon a line that is transverse to aflow of exhaust through the nozzle 66. The line is also not aligned withthe sides 94 and 96 of the member 82. Though the throat A8 is shown asextending in a straight line, other shapes of extension are alsocontemplated. For example, the throat A8 may lie upon a convex orcurvilinear line between sides of the nozzle 66. Any variety of otherconfigurations are also contemplated within the scope of the instantapplication. Though the throat area A8 is discussed in this particularembodiment, similar configurations can also provide similar arrangementsof the throat area A28.

As will be appreciated, given the description above certain modes ofoperation will be apparent. At cruise conditions, which can be subsonic,the engine 50 can be configured in an SFC mode in which the member 80 isplaced in a relatively aft position while the member 82 is positioned topermit flow through the flow area 102. In a maximum power setting, noafterburning, setting, the member 80 can be placed in a relativelyforward position and the member 82 positioned to close the flow area102. In a maximum afterburning mode the member 80 can be placedrelatively aft position and the member 82 positioned to either close theflow area 102 or open it slightly to provide for cooling. Other powersettings and member positions are also contemplated herein.

An aspect of the present application includes an apparatus comprising avariable cycle gas turbine engine having a core flow passage and abypass passage, and a nozzle oriented to merge the core flow passage andthe bypass passage, the nozzle including a first slideable member and asecond slideable member defining the core flow passage, the secondslideable member also defining the bypass passage.

A feature of the present application includes wherein the bypass passageis a third stream bypass passage structured to withdraw a working fluidfrom a fan bypass passage.

Another feature of the present application includes wherein a portion ofworking fluid traversing the third stream bypass passage is split into afirst branch bypass passage and a second branch bypass passage, thefirst branch bypass passage forming the bypass passage merged with thecore flow passage in the nozzle.

Still another feature of the present application further includes anopening for discharge of working fluid from the third stream bypasspassage into the nozzle upstream from an exit of the nozzle.

Yet still another feature of the present application includes whereinthe opening is formed on a lateral side of the nozzle.

Still yet another feature of the present application includes whereinthe nozzle receives a merged flow from the core flow passage and a fanbypass passage, the first slideable member and the second slideablemember defining a merged flow passage from the core flow passage and thefan bypass passage.

A further feature of the present application includes wherein the fanbypass passage is annular.

A still further feature of the present application includes wherein thethird stream bypass passage is an annular passage at an upstream portionof the variable cycle gas turbine engine, and wherein the third streambypass passage is split to transition from the annular passage to anunderslung passage.

Yet a still further feature of the present application further includesan third stream bypass passage, the nozzle oriented to merge the coreflow passage and the fan bypass passage.

Still yet a further feature of the present application includes whereinthe first slideable member is disposed on one side of the core flowpassage and the second slideable member is disposed on another side ofthe core flow passage.

Yet another feature of the present application includes wherein the coreflow passage and fan bypass passage are coaxial at an upstream locationof the gas turbine engine, wherein the fan bypass passage is unwrappedfrom the coaxial axis between the upstream location and the nozzle suchthat the bypass passage is laterally displaced from the core flowpassage.

Still yet another feature of the present application further includes aheat exchanger disposed in the bypass passage.

Another feature of the present application includes wherein the secondslideable member includes a contour that changes as a function of buttline.

A still further feature of the present application includes wherein thetrailing edge of the second slideable member is at an angle relative toa reference line of the gas turbine engine.

Still another feature of the present application includes wherein thetrailing edge of the second slideable member includes a first portion ata first angle to a reference line of the gas turbine engine and anopposing second portion at a second angle to the reference line.

Yet still another feature of the present application includes wherein athroat of the bypass passage is defined by the second slideable member,and wherein the throat has a contour different than a trailing edge ofthe second slideable member.

Still yet another feature of the present application includes wherein athroat of the bypass passage is defined by the second slideable member,and wherein the throat has a contour different than a trailing edge ofan exit of the nozzle.

Another aspect of the present application includes an apparatuscomprising a gas turbine engine having a core flow passage, annularshaped third stream bypass passage unwrapped from coaxial axis andducted to an underslung configuration, a branch of the ducted thirdstream bypass configured to withdraw working fluid from the third streambypass passage downstream of the unwrap location; a nozzle that receivesa working fluid from the core flow passage and from the third streambypass passage, the nozzle configurable to change a flow area of thecore flow passage and a flow area of the third stream bypass passage bymovement of a first member and second member.

A feature of the present application includes wherein the core flowpassage includes a flow from a core of the gas turbine engine and from aturbofan of the gas turbine engine.

Still another feature of the present application includes wherein thefirst member is configured to be slideably moveable from an openposition to a closed position.

Yet still another feature of the present application includes whereinthe first member is slideably moveable along an axis that is at an anglerelative to an axis that the second member is slideably moveable along.

Still yet another feature of the present application includes whereinthe core flow passage is defined between the first member and the secondmember.

A further feature of the present application includes wherein the thirdstream bypass passage is defined between a fixed portion of the nozzleand the second member.

A still further feature of the present application includes wherein thenozzle receives a first branch flow from the third stream bypass passageand a second branch flow from the third stream bypass passage, the firstbranch flow traversing the changeable flow area of the third streambypass passage.

A yet still further feature of the present application includes whereinthe second branch flow from the third stream bypass passage is receivedin the nozzle through an opening.

Yet another feature of the present application includes wherein a heatexchanger is disposed within the second branch.

Still yet another feature of the present application includes whereinthe opening is through a lateral wall of the nozzle.

Yet still another feature of the present application includes whereinthe opening is through a deck of the nozzle.

A yet further feature of the present application includes wherein thenozzle includes a single expansion ramp nozzle.

Yet another feature of the present application further includes a splitand re-merge of flow between upstream and downstream end of fan flowpassage.

Still yet another feature of the present application includes whereinthe nozzle includes an outlet having a non-linear downstream edge.

A further feature of the present application includes wherein thenon-linear downstream edge includes a first edge and a second edgedisposed at an angle relative to each other.

A still further feature of the present application includes wherein atleast one of the first member and second member includes a downstreamedge parallel to the downstream edge of the nozzle.

A yet further feature of the present application includes wherein theflow area of the core flow passage includes a throat of the core flowpassage, the throat extending between side walls of the nozzle in aconfiguration different from the downstream edge of the nozzle.

Still another feature of the present application includes wherein atleast one of the first member and second member include a cross sectionthat varies laterally between side walls of the nozzle.

Yet another aspect of the present application provides a methodcomprising operating a gas turbine engine having a core flow path and abypass path, ducting the bypass path from an annular passage to anlaterally displaced passage that extends partially around the gasturbine engine, and sliding a first nozzle member to change a firstnozzle flow area through which a working fluid from the core flow pathtraverses.

A feature of the present application further includes withdrawing athird stream bypass from a fan bypass of the gas turbine engine.

Another feature of the present application further includes sliding asecond nozzle member to change a second nozzle flow area through which aworking fluid from the bypass path traverses.

Still another feature of the present application includes wherein thefirst nozzle area through which the working fluid from the core flowpath traverses is also changed by movement of the second nozzle member.

Yet still another feature of the present application includes whereinthe bypass path includes a first branch of a third stream bypass path, asecond branch of the third stream bypass path routed to a separatelocation in the nozzle.

Still yet another feature of the present application further includesexchanging heat between a working fluid in the second branch of thethird stream bypass path with a heat exchanger in thermal communicationwith a component.

Yet still another feature of the present application further includesmoving the first nozzle member from a forward position to a rearwardposition when the gas turbine engine is transitioned between a cruisemode and a max thrust mode.

Still yet another feature of the present application further includesactuating the first nozzle member to slide from a rearward position to aforward position when the gas turbine engine is requested to transitionfrom a dry thrust mode to an afterburning mode.

Yet a further feature of the present application further includesopening the second nozzle flow area during an afterburning mode.

Still yet a further feature of the present application includes whereinthe opening of the second nozzle flow area occurs when the second nozzlemember slides within a plane oriented at an angle to an axial axis ofthe gas turbine engine

Yet still a further feature of the present application further includesconverging a flow of working fluid through a throat that extends in adifferent direction than an exit edge of the nozzle.

Yet another feature of the present application further includes coolinga deck of the nozzle using a working fluid from the bypass path.

Still another aspect of the present application includes an apparatuscomprising a variable cycle gas turbine engine having a core flowpassage, a fan bypass passage, and a third stream bypass passage, and anozzle oriented to merge the core flow passage and the third streambypass passage, the nozzle including a first slideable member and asecond slideable member defining the core flow passage, the secondslideable member also defining the bypass passage.

A feature of the present application includes wherein a portion ofworking fluid traversing the third stream bypass passage is split into afirst branch bypass passage and a second branch bypass passage, thefirst branch bypass passage forming the bypass passage merged with thecore flow passage in the nozzle.

Another feature of the present application includes wherein the nozzlereceives a merged flow from the core flow passage and a fan bypasspassage, the first slideable member and the second slideable memberdefining a merged flow passage from the core flow passage and the fanbypass passage.

Still another feature of the present application includes wherein thethird stream bypass passage is an annular passage at an upstream portionof the variable cycle gas turbine engine, and wherein the third streambypass passage is split to transition from the annular passage to anunderslung passage.

Yet still another feature of the present application further includes aheat exchanger disposed in the third stream bypass passage.

Still yet another feature of the present application includes whereinthe second slideable member includes a contour that changes as afunction of butt line.

A further feature of the present application includes wherein a trailingedge of the second slideable member includes a first portion at a firstangle to a reference line of the gas turbine engine and an opposingsecond portion at a second angle to the reference line.

A still further feature of the present application includes wherein athroat of the third stream bypass passage is defined by the secondslideable member, and wherein the throat has a contour different than atrailing edge of the second slideable member.

A still further feature of the present application includes wherein thethroat has a contour different than a trailing edge of an exit of thenozzle.

A further aspect of the present application includes an apparatuscomprising a gas turbine engine having a core flow passage, an annularshaped third stream bypass passage unwrapped from coaxial axis andducted to an underslung configuration, a branch of the third streambypass passage configured to withdraw working fluid from the thirdstream bypass passage downstream of the unwrap location, and a nozzlethat receives a working fluid from the core flow passage and from thethird stream bypass passage, the nozzle configurable to change a flowarea of the core flow passage and a flow area of the third stream bypasspassage by movement of a first member and second member.

A feature of the present application includes wherein the first memberis slideably moveable along an axis that is at an angle relative to anaxis that the second member is slideably moveable along.

Another feature of the present application includes wherein the coreflow passage is defined between the first member and the second member,and wherein the third stream bypass passage is defined between a fixedportion of the nozzle and the second member.

Still another feature of the present application includes wherein thenozzle receives a first branch flow from the third stream bypass passageand a second branch flow from the third stream bypass passage.

Yet still another feature of the present application includes wherein aheat exchanger is disposed within a second branch.

Still yet another feature of the present application includes whereinthe first branch flow is received into the nozzle through a lateral wallof the nozzle.

Yet still another feature of the present application includes whereinthe first branch flow is received into the nozzle through a deck of thenozzle.

A further feature of the present application includes wherein the nozzleincludes a single expansion ramp nozzle.

A yet further feature of the present application includes wherein thenozzle includes a first edge and a second edge disposed at an anglerelative to each other.

A still further feature of the present application includes wherein atleast one of the first member and second member include a cross sectionthat varies laterally between side walls of the nozzle.

Still a yet further aspect of the present application includes a methodcomprising operating a gas turbine engine having a core flow path and abypass path, withdrawing a third stream bypass from a fan bypass of thegas turbine engine, ducting the third stream bypass from an annularpassage to an laterally displaced passage that extends partially aroundthe gas turbine engine, and sliding a first nozzle member to change afirst nozzle flow area through which a working fluid from the core flowpath traverses.

A feature of the present application further includes sliding a secondnozzle member to change a second nozzle flow area through which aworking fluid from the bypass path traverses.

Another feature of the present application includes wherein the firstnozzle flow area through which the working fluid from the core flow pathtraverses is also changed by movement of the second nozzle member.

Still another feature of the present application includes wherein thethird stream bypass includes a first branch and a second branch routedto separate locations in the nozzle.

Yet still another feature of the present application further includesexchanging heat between a working fluid in the second branch of thethird stream bypass with a heat exchanger in thermal communication witha component.

Still yet another feature of the present application further includesmoving the first nozzle member from a forward position to a rearwardposition when the gas turbine engine is transitioned between a cruisemode and a max thrust mode.

Yet still another feature of the present application further includesactuating the first nozzle member to slide from a rearward position to aforward position when the gas turbine engine is requested to transitionfrom a dry thrust mode to an afterburning mode.

Still yet another feature of the present application further includesopening a second nozzle flow area during the afterburning mode, andwherein the opening of the second nozzle flow area occurs when thesecond nozzle member slides within a plane oriented at an angle to anaxial axis of the gas turbine engine.

An aspect of the present application provides an apparatus comprising avariable cycle gas turbine engine having a core flow passage, a fanbypass passage, and a third stream bypass passage, and a nozzle orientedto merge the core flow passage and the third stream bypass passage, thenozzle including a first slideable member and a second slideable memberdefining a first flow area through which passes flow from the core flowpassage, the second slideable member also defining a third stream flowarea of the third stream bypass passage, wherein the second slideablemember is capable of changing a flow area of both the first flow areaand the third stream flow area.

A feature of the present application further provides wherein a portionof working fluid traversing the third stream bypass passage is splitinto a first branch bypass passage and a second branch bypass passage,the first branch bypass passage forming the bypass passage merged withthe core flow passage in the nozzle.

Another feature of the present application further provides wherein thenozzle receives a merged flow from the core flow passage and a fanbypass passage, the first slideable member and the second slideablemember defining a merged flow passage from the core flow passage and thefan bypass passage.

Still another feature of the present application further provideswherein the third stream bypass passage is an annular passage at anupstream portion of the variable cycle gas turbine engine, and whereinthe third stream bypass passage is split to transition from the annularpassage to an underslung passage.

Yet still another feature of the present application further provides aheat exchanger disposed in the third stream bypass passage.

Still yet another feature of the present application further provideswherein the second slideable member includes a contour that changes as afunction of butt line.

A further feature of the present application further provides wherein atrailing edge of the second slideable member includes a first portion ata first angle to a reference line of the gas turbine engine and anopposing second portion at a second angle to the reference line.

Still a further feature of the present application further provideswherein a throat of the third stream bypass passage is defined by thesecond slideable member, and wherein the throat has a contour differentthan a trailing edge of the second slideable member.

Yet still a further feature of the present application further provideswherein the throat has a contour different than a trailing edge of anexit of the nozzle.

Another aspect of the present application provides an apparatuscomprising a gas turbine engine having a core flow passage and a fanbypass passage that together are merged into a merged flow passage, anannular shaped third stream bypass passage unwrapped from coaxial axisand ducted to an underslung configuration to form a third stream nozzlepassage, and a nozzle that receives the merged flow passage and thethird stream nozzle passage, the nozzle having a dual-use moveablemember disposed between the merged flow passage and the third streamnozzle passage and structured to dependently change an area of themerged flow passage and the third stream nozzle passage whereby movementof the dual-use moveable member can increase a flow area of the mergedflow passage while it decreases a flow area of the third stream nozzlepassage.

A feature of the present application further provides a single-usemoveable member that defines the merged flow passage.

Another feature of the present application further provides wherein thesingle-use moveable member and the dual-use moveable member can togetherdefine a flow are of the merged flow passage, and wherein the dual-usemoveable member is translatable along an axis.

Still another feature of the present application further provideswherein the single-use moveable member is translatable between arelatively open position and a relatively closed position.

Yet still another feature of the present application further provideswherein the dual-use moveable member is translatingly moveable along anaxis of extension.

Still yet another feature of the present application further provideswherein the dual-use moveable member includes a cross section thatvaries with butt-line, and wherein the axis of extension that thedual-use moveable member is translatingly moveable is disposed at anangle to an axis of extension over which the single-use moveable memberis translatable.

A further feature of the present application further provides whereinthe single-use moveable member is translatable along a first axis thatis oriented at an angle to an axis along which the dual-use moveablemember is translatable.

A still further feature of the present application further provideswherein the nozzle includes a single expansion ramp nozzle.

Yet still a further feature of the present application further includesa third stream branch that receives working fluid from the annularshaped third stream bypass passage separate from the working fluidreceived in the third stream nozzle passage.

Still another feature of the present application further provideswherein the third stream branch delivers its working fluid to the nozzledownstream of the dual-use moveable member.

Another aspect of the present application provides a method comprisingoperating a gas turbine engine having a core flow path, a bypass path,and a third stream bypass path, ducting the third stream bypass pathfrom an annular-shaped passage to a laterally displaced passage thatextends partially around the gas turbine engine, and moving a firstnozzle member to change a first nozzle flow area through which a workingfluid from the core flow path traverses, and adjusting a second nozzlemember in a different manner than the moving to alter a third streamarea through which a working fluid from the third stream passes, andmerging the working fluid from the core flow path with the working fluidfrom the third stream.

A feature of the present application further provides wherein theadjusting includes sliding the second nozzle member to alter the thirdstream flow area.

Another feature of the present application further provides wherein thefirst nozzle flow area through which the working fluid from the coreflow path traverses is also changed by the adjusting of the secondnozzle member.

Still another feature of the present application further provideswherein the different manner includes sliding the second nozzle memberin a non-coincident manner to the moving the first nozzle member, andwherein the third stream bypass path includes a first branch and asecond branch routed to separate locations in a nozzle that includes thefirst nozzle member and the second nozzle member.

Yet still another feature of the present application further includesexchanging heat between a working fluid in a branch of the third streambypass path with a heat exchanger in thermal communication with acomponent.

Still yet another feature of the present application further includesmoving the first nozzle member from a forward position to a rearwardposition when the gas turbine engine is transitioned between a cruisemode and a max thrust mode.

A further feature of the present application further includes actuatingthe first nozzle member to slide from a rearward position to a forwardposition when the gas turbine engine is requested to transition from adry thrust mode to an afterburning mode.

Still another feature of the present application further includesopening a second nozzle flow area during the afterburning mode, andwherein the opening of the second nozzle flow area occurs when thesecond nozzle member slides within a plane oriented at an angle to anaxial axis of the gas turbine engine.

Still another aspect of the present application provides an apparatuscomprising a gas turbine engine having a core flow passage, fan bypasspassage, and a third stream bypass passage, a branch of the third streambypass passage configured to withdraw working fluid from the thirdstream bypass passage and extending downstream from a branch point, thebranch of the third stream passage forming a separate flow path from thethird stream passage, the branch of the third stream passage configuredto have attenuated fluctuations in flow rate relative to fluctuations inflow rate of the third stream bypass passage at a location downstream ofthe branch point, a nozzle that receives a working fluid from a mergerof the core flow passage and the fan bypass passage as well as a workingfluid from the third stream bypass passage, the nozzle configurable tochange a flow area of the merger of the core flow passage and fan bypasspassage, and a heat exchanger located in the branch such that therelatively consistent flow rate of working fluid through the branch isused to exchange heat with the heat exchanger.

A feature of the present application provides wherein a heat exchangeris disposed within the branch of the third stream bypass passage.

Another feature of the present application provides wherein the nozzlereceives a first branch flow from the third stream bypass passage and asecond branch flow from the third stream bypass passage.

Still another feature of the present application provides wherein thethird stream bypass passage includes an annular configuration that isunwrapped from coaxial axis and ducted to an underslung configuration.

Still yet another feature of the present application provides whereinflow from the branch is received into the nozzle through a lateral wallof the nozzle.

Yet still another feature of the present application provides whereinthe first branch flow is received into the nozzle through a deck of thenozzle.

A further feature of the present application provides wherein the nozzleis also configurable to change a flow are of the third stream bypasspassage.

A still further feature of the present application provides wherein thenozzle includes a single expansion ramp nozzle, wherein the flow area ofthe merger of the core flow passage and the fan bypass passage as wellas the flow area of the third stream bypass passage is via movement of afirst member, and which further includes a second member used to changea flow area of the core flow passage, and wherein the first member isslideably moveable along an axis that is at an angle relative to an axisthat the second member is slideably moveable along.

A yet still further feature of the present application provides whereinthe nozzle includes a serrated exit surface, and wherein the thirdstream bypass passage is defined between a fixed portion of the nozzleand the second member.

Still yet a further feature of the present application further includesa first nozzle member and a second nozzle member, and wherein at leastone of the first nozzle member and second nozzle member include a crosssection that varies laterally between side walls of the nozzle.

Yet another aspect of the present application provides an apparatuscomprising a gas turbine engine having a core flow passage and a fanbypass passage, a third stream bypass passage having an annularconfiguration at an upstream location, a split in the annularconfiguration at a location intermediate an upstream position of thethird stream bypass passage and a downstream location of the thirdstream bypass passage such that the third stream bypass passage isradially displaced to the side of the core flow passage downstream ofthe split, a flow partition located in the third stream bypass passagestructured to form a nozzle path of the third stream bypass passage anda utility path of the third stream bypass passage, a nozzle thatreceives a working fluid from the core flow passage, the fan bypasspassage, and from the nozzle path of the third stream bypass passage,and wherein the utility path of the third stream bypass passage isconfigured to accommodate a thermodynamic device structured tothermodynamically alter a working fluid flowing through the secondbranch.

A feature of the present application provides wherein the flow partitionlocated downstream of the split in the annular configuration.

Another feature of the present application provides wherein thethermodynamic device is a heat exchanger.

Still another feature of the present application provides wherein theutility path of the third stream bypass passage is structured tomaintain a relatively consistent flow rate over a range of engineoperating conditions in comparison to a flow rate of working fluidthrough the nozzle path.

Yet still another feature of the present application provides whereinthe flow rate of working fluid through the nozzle path can include arate that results from closing the nozzle path.

Still yet another feature of the present application further includes asecond utility path of the third stream bypass passage.

A further feature of the present application provides wherein the nozzleincludes a first slidable member defining a merger of the core flowpassage and the fan bypass passage, and a second slidable memberdefining the merger.

Still another aspect of the present application provides a methodcomprising operating a gas turbine engine having a core flow path and afan bypass path, flowing a working fluid through a third stream bypasspassage, branching a path from the third stream bypass passage,maintaining a relatively constant flow rate of working fluid through thebranch, and transferring energy between the relatively constant flowrate through the branch and a thermodynamic device disposed within thebranch.

A feature of the present application further includes actuating amoveable member that can vary a flow area of the third stream bypasspassage and thereby affect the flow rate of the working fluid.

Another feature of the present application further includes ductingworking fluid from an annular configuration in the third stream bypasspassage to a laterally displaced configuration in the third streambypass passage.

Still another feature of the present application provides wherein thethermodynamic device is a heat exchanger, and wherein the actuating themoveable member also varies a flow area of a merged flow passage thatincludes the core flow path and the bypass flow path.

Yet still another feature of the present application further includesmoving a second moveable member to alter a flow area of the merged flowpassage.

Another aspect the present application provides an apparatus comprisinga gas turbine engine having a core flow passage and a rotatableturbomachinery component that operates upon working fluid in a bypasspassage, the bypass passage having a branch configured to convey aportion of working fluid traversing the bypass passage and a variablegeometry flow mechanism configured to change a flow area, the variablegeometry flow mechanism capable of being commanded at different enginepower settings by a controller to a configuration that provides forattenuated fluctuations in flow rate within the branch relative tovariations in flow rate provided by the different engine power settingsof any remaining working fluid in the bypass passage that is notconveyed by the branch, and a utility device located in thermodynamiccommunication with the working fluid conveyed through the branch suchthat the relatively consistent flow rate of working fluid through thebranch is used to exchange energy with the utility device.

A feature of the present application provides wherein the variablegeometry flow mechanism is coupled with the bypass passage to change theflow area of the bypass passage.

Another feature of the present application provides wherein a flow areaof the branch can be changed as a result of a command provided by thecontroller, and wherein the variable geometry flow mechanism istranslatingly moved from a first position to a second position uponreceipt of a command from the controller.

Still another feature of the present application further includesanother variable geometry flow mechanism coupled with the branch,wherein the bypass passage is a third stream bypass passage of aturbofan engine, and wherein the rotatable turbomachinery componentprovides working fluid for both the core flow passage and the bypasspassage.

Yet still another feature of the present application provides whereinthe utility device is a heat exchanger having a thermal member exposedto working fluid within the branch of the bypass passage, wherein thevariable geometry flow mechanism is moved along an axis as it changesthe flow area, and wherein the controller receives information derivedfrom a sensor to assist in determining a command for the variablegeometry flow mechanism.

Still yet another feature of the present application provides whereinthe gas turbine engine includes a fan bypass passage, wherein the bypasspassage is a third stream bypass passage, and wherein the core flowpassage and the fan bypass passage are merged.

A further feature of the present application provides wherein the thirdstream bypass passage is configurable such that a flow area of the thirdstream bypass passage can be changed, and wherein a common nozzle isstructured to receive working fluid from the core flow passage, fanbypass passage, and third stream bypass passage.

Still a further feature of the present application provides wherein aflow area of the merged core flow passage and fan bypass passage as wellas the flow area of the third stream bypass passage is via movement ofthe variable geometry flow mechanism, and which further includes anothervariable geometry flow mechanism used to change flow area of the mergedcore flow passage and fan bypass passage, and wherein the variablegeometry flow mechanism is slideably moveable along an axis that is atan angle relative to an axis that the another variable geometry flowmechanism is slideably moveable along.

Yet still a further feature of the present application provides whereina common nozzle includes the variable geometry flow mechanism and theanother variable geometry flow mechanism, and wherein the common nozzleis also structured to receive working fluid from the branch.

Still yet a further feature of the present application provides whereinthe branch includes a branch variable geometry flow mechanism structuredto change a flow area of the branch.

Yet still another feature of the present application provides whereinthe variable geometry flow mechanism includes a first nozzle member andthe another variable geometry flow mechanism includes a second nozzlemember, and wherein at least one of the first nozzle member and secondnozzle member include a cross section that varies laterally between sidewalls of a common nozzle structured to flow both the third stream bypasspassage and the merged core flow passage and fan bypass passage.

Yet another aspect of the present application provides an apparatuscomprising a gas turbine engine having a core flow passage and a bypasspassage that is located downstream of a rotatable bladed component, aflow partition located in the bypass passage structured to form a firstpath of the bypass passage and a utility path of the bypass passage, avariable geometry device coupled with one of the first path of thebypass passage and the utility path of the bypass passage, the variablegeometry device responsive to changes in operating condition of the gasturbine engine such that the variable geometry device provides asubstantially constant flow rate of working fluid through the utilitypath of the bypass passage over a range of operating conditions of thegas turbine engine, and wherein the utility path of the bypass passageis configured to accommodate a thermodynamic device structured tothermodynamically alter a working fluid flowing through the utilitypath.

A feature of the present application provides wherein the variablegeometry device is coupled with the first path of the bypass passage andis structured to change a flow area of the first path of the bypasspassage.

Another feature of the present application provides wherein therotatable bladed component provides working fluid to both the core flowpassage and the bypass passage.

Still another feature of the present application provides wherein thegas turbine engine is a turbofan engine, wherein the bypass passage is athird stream bypass passage, and wherein the thermodynamic device is aheat exchanger.

Yet still another feature of the present application provides whereinthe third stream bypass passage is an annular offtake from a fan bypasspassage of the turbofan engine, and wherein the flow partition issituated to circumferentially split working fluid flowing in the thirdstream bypass passage.

A further feature of the present application provides wherein theannular shaped third stream bypass passage further includes a splitlocated upstream of the flow partition, the third stream bypass passageincluding a transition region downstream of the split that ducts thethird stream bypass passage into a radially displaced passage relativeto the core flow passage.

A still further feature of the present application further includes acontroller structured to receive a signal used to determine a command tothe variable geometry device, the controller operable to generate acommand signal for use by an actuation device, and wherein the utilitypath is coupled with another variable geometry device structured tochange a flow area of the utility path.

Yet a still further feature of the present application further includesa nozzle through which passages core flow of the gas turbine engine.

Yet another feature of the present application provides wherein thenozzle is further structured to receive working fluid from a fan bypasspassage of the gas turbine engine, and wherein the bypass passage is athird stream bypass passage.

Still yet another feature of the present application provides whereinthe nozzle is further structured to receive working fluid from the thirdstream bypass passage, and which further includes a fan and corevariable geometry device configured to change a flow area of a mergedflow passage between the fan bypass passage and the core flow passage.

A further feature of the present application provides wherein thevariable geometry device is operable to change flow area of both thethird stream bypass passage and the merged flow passage, and wherein thenozzle is structured to receive working fluid from the utility path ofthe bypass passage.

Still yet another aspect of the present application provides a methodcomprising operating a gas turbine engine having a core flow path and abypass path to convey working fluid through the bypass path, branchingworking fluid from the bypass path to form a flow of working fluid in abranch path, transferring an energy between the flow of working fluidthrough the branch path and a thermodynamic device disposed incommunication with the branch path, and changing a flow area of at leastone of the bypass path and the branch path as a result of a change inoperating condition of the gas turbine engine, the changing in responseto maintaining a flow rate of working fluid through the branch path thatis adequate for the transferring.

A feature of the present application provides wherein the changing aflow area includes actuating a moveable member that can vary a flow areaof the bypass path.

Another feature of the present application provides wherein the bypasspath is a third stream bypass path, and wherein the gas turbine enginefurther includes a fan bypass path, and wherein the changing affects aflow area of the third stream bypass path.

Still another feature of the present application provides wherein thethermodynamic device is a heat exchanger, and which further includesaltering a flow area of the branch path from the third stream bypasspath.

Yet still another feature of the present application further includesmerging the third stream bypass path, core flow path, and fan bypasspath in a common nozzle.

A further feature of the present application provides wherein themerging further includes directing the branch path of the third streambypass path to be received by the common nozzle.

Still yet another aspect of the present application provides anapparatus comprising a gas turbine engine having a core flow passage anda rotatable turbomachinery component that operates upon working fluid ina bypass passage, the bypass passage having a branch configured toconvey a portion of working fluid traversing the bypass passage and avariable geometry flow mechanism configured to change a flow area, thevariable geometry flow mechanism capable of being commanded at differentengine power settings by a controller to a configuration that providesfor a utility flow rate within the branch, and a utility device locatedin thermodynamic communication with the working fluid conveyed throughthe branch such that the working fluid exchanges energy with the utilitydevice, the utility flow rate a function of an energy exchangerequirement of the utility device.

Yet still another aspect of the present application provides anapparatus comprising a gas turbine engine having a core flow passage anda bypass passage that is located downstream of a rotatable bladedcomponent, a flow partition located in the bypass passage structured toform a first path of the bypass passage and a utility path of the bypasspassage, a variable geometry device coupled with one of the first pathof the bypass passage and the utility path of the bypass passage,wherein the utility path of the bypass passage is configured toaccommodate a thermodynamic device structured to thermodynamically altera working fluid flowing within the utility path, and wherein thevariable geometry device responsive to changes in operating condition ofthe gas turbine engine such that the variable geometry device is set ata configuration to accommodate a demand for energy exchange over a rangeof operating conditions of the gas turbine engine and demand of thethermodynamic device.

Still another aspect of the present application provides an apparatuscomprising a gas turbine engine having a core flow passage, a fan bypasspassage, and a third stream bypass passage that is split from the fanbypass passage, the third stream bypass passage having a branchconfigured to convey a portion of working fluid traversing the thirdstream bypass passage, and a heat exchanger located in thermalcommunication with the working fluid conveyed through the branch of thethird stream bypass passage such that the working fluid exchanges heatwith the heat exchanger.

A feature of the present application further includes a variablegeometry flow mechanism configured to change a flow area of the thirdstream bypass passage, the variable geometry flow mechanism capable ofbeing commanded at different engine power settings by a controller to aconfiguration that provides for a utility flow rate within the branch,the utility flow rate a function of a heat exchange requirement of theheat exchanger.

Another feature of the present application provides wherein the variablegeometry flow mechanism is configured to change the flow area of thebranch.

Still another feature of the present application provides wherein thevariable geometry flow mechanism is configured to change the flow areaof the third stream bypass passage separate from the branch at alocation downstream of a branch point that begins the branch.

Yet still another feature of the present application provides whereinthe branch includes a fixed geometry such that it remains in the sameconfiguration throughout the branch during operation of the gas turbineengine.

Still yet another feature of the present application provides whereinthe third stream bypass passage that conveys working fluid that is notrouted through the branch includes a fixed geometry such that it remainsin a static configuration.

A further feature of the present application provides wherein the heatexchanger is located at an upstream end of the branch.

Yet a further feature of the present application provides wherein thethird stream bypass passage includes an exit set apart from an exit ofthe fan bypass passage.

Still yet a further feature of the present application provides whereinthe third stream bypass passage includes a discharge location that iswithin a region of influence of a discharge location associated with thefan bypass passage.

Another aspect of the present application provides an apparatuscomprising a turbofan engine having a core flow passage, a fan bypasspassage, and a third stream bypass passage that is located downstream ofa rotatable bladed component, a flow partition located in the thirdstream bypass passage structured to form a first path of the thirdstream bypass passage and a utility path of the third stream bypasspassage, and wherein the utility path of the third stream bypass passageis configured to accommodate a heat exchanger structured to thermallyalter a working fluid flowing within the utility path.

A feature of the present application further includes a variablegeometry device coupled with one of the first path of the third streambypass passage and the utility path of the third stream bypass passage.

Another feature of the present application provides wherein the variablegeometry device is coupled with both of the first path and the utilitypath.

Still another feature of the present application provides wherein thefirst path has a fixed end in proximity to an exit of the first path.

Yet still another feature of the present application provides whereinthe utility path has a fixed end in proximity to an exit of the utilitypath.

Still yet another feature of the present application provides whereinthe variable geometry device is responsive to changes in operatingcondition of the gas turbine engine such that the variable geometrydevice is set at a configuration to provide a flow rate thataccommodates a demand for heat exchange between the heat exchanger andthe working fluid flowing in the utility path over a range of operatingconditions of the gas turbine engine.

A further feature of the present application provides wherein the heatexchanger is located upstream from an exit of the utility path of thethird stream bypass passage.

A still further feature of the present application provides wherein anexit of the utility path and an exit of the first path of the thirdstream bypass passage are distinct exits to an external space and thatare located apart from each other.

A yet still further feature of the present application provides whereinworking fluid discharged from the utility path is influenced by workingfluid discharged from the first path of the third stream bypass passage

Still yet another aspect of the present application provides a methodcomprising operating a gas turbine engine having a core flow path, a fanbypass path, and a third stream bypass path to convey working fluidthrough the third stream bypass path, branching working fluid from thethird stream bypass path to form a flow of working fluid in a branchpath, and transferring an energy between the flow of working fluidthrough the branch path and a heat exchanger disposed in communicationwith the branch path.

A feature of the present application further includes changing a flowarea of at least one of the third stream bypass path and the branch pathas a result of a change in operating condition of the gas turbineengine, the changing in response to maintaining a flow rate of workingfluid through the branch path that is adequate for the transferring.

Another feature of the present application further includes dischargingworking fluid from the third stream bypass path and working fluid in thebranch path to an external location in a manner in which the dischargingmutually influences each of the working fluid in the third stream bypasspath and the branch path.

Still another feature of the present application provides whereinworking fluid exiting the third stream bypass path and the branch pathare through independent exits.

Yet still another feature of the present application further includesflowing working fluid through a fixed downstream end of at least one ofthe third stream bypass path and the branch path.

A further feature of the present application provides wherein theflowing is through a fixed downstream end of both the third streambypass path and the branch path.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiments have been shown and described and thatall changes and modifications that come within the spirit of theinventions are desired to be protected. It should be understood thatwhile the use of words such as preferable, preferably, preferred or morepreferred utilized in the description above indicate that the feature sodescribed may be more desirable, it nonetheless may not be necessary andembodiments lacking the same may be contemplated as within the scope ofthe invention, the scope being defined by the claims that follow. Inreading the claims, it is intended that when words such as “a,” “an,”“at least one,” or “at least one portion” are used there is no intentionto limit the claim to only one item unless specifically stated to thecontrary in the claim. When the language “at least a portion” and/or “aportion” is used the item can include a portion and/or the entire itemunless specifically stated to the contrary.

What is claimed is:
 1. An apparatus comprising: a gas turbine enginehaving a core flow passage, a fan bypass passage, and a third streambypass passage that is split from the fan bypass passage to divert aportion of the working fluid traversing the fan bypass away from the fanbypass, the third stream bypass passage having a flow divider thatdefines a first branch and a second branch, the first and secondbranches configured to convey a portion of working fluid traversing thethird stream bypass passage; and a heat exchanger located in thermalcommunication with the working fluid conveyed through the first branchof the third stream bypass passage such that the working fluid exchangesheat with the heat exchanger.
 2. The apparatus according to claim 1,which further includes a variable geometry flow mechanism configured tochange a flow area of the third stream bypass passage, the variablegeometry flow mechanism capable of being commanded at different enginepower settings by a controller to a configuration that provides for autility flow rate within the branch, the utility flow rate a function ofa heat exchange requirement of the heat exchanger.
 3. The apparatusaccording to claim 2, wherein the variable geometry flow mechanism isconfigured to change the flow area of the branch.
 4. The apparatusaccording to claim 2, wherein the variable geometry flow mechanism isconfigured to change the flow area of the third stream bypass passageseparate from the branch at a location downstream of a branch point thatbegins the branch.
 5. The apparatus according to claim 1, wherein thebranch includes a fixed geometry such that it remains in the sameconfiguration throughout the branch during operation of the gas turbineengine.
 6. The apparatus according to claim 1, wherein the third streambypass passage that conveys working fluid that is not routed through thebranch includes a fixed geometry such that it remains in a staticconfiguration.
 7. The apparatus according to claim 1, wherein the heatexchanger is located at an upstream end of the branch.
 8. The apparatusaccording to claim 1, wherein the third stream bypass passage includesan exit set apart from an exit of the fan bypass passage.
 9. Theapparatus according to claim 1, wherein the third stream bypass passageincludes a discharge location that is within a region of influence of adischarge location associated with the fan bypass passage.
 10. Anapparatus comprising: a turbofan engine having a core flow passage, afan bypass passage, and a third stream bypass passage that is locateddownstream of a rotatable bladed component the third stream bypassstructured to receive a portion of flow from the fan bypass passage—hasbeen inserted after “component”; a flow partition located in the thirdstream bypass passage structured to form a first path of the thirdstream bypass passage and a utility path of the third stream bypasspassage; and wherein the utility path of the third stream bypass passageis configured to accommodate a heat exchanger structured to thermallyalter a working fluid flowing within the utility path.
 11. The apparatusof claim 10, which further includes a variable geometry device coupledwith one of the first path of the third stream bypass passage and theutility path of the third stream bypass passage.
 12. The apparatus ofclaim 11, wherein the variable geometry device is coupled with both ofthe first path and the utility path.
 13. The apparatus of claim 10,wherein the first path has a fixed end in proximity to an exit of thefirst path.
 14. The apparatus of claim 10, wherein the utility path hasa fixed end in proximity to an exit of the utility path.
 15. Theapparatus of claim 11, wherein the variable geometry device isresponsive to changes in operating condition of the gas turbine enginesuch that the variable geometry device is set at a configuration toprovide a flow rate that accommodates a demand for heat exchange betweenthe heat exchanger and the working fluid flowing in the utility pathover a range of operating conditions of the gas turbine engine.
 16. Theapparatus of claim 10, wherein the heat exchanger is located upstreamfrom an exit of the utility path of the third stream bypass passage. 17.The apparatus of claim 10, wherein an exit of the utility path and anexit of the first path of the third stream bypass passage are distinctexits to an external space and that are located apart from each other.18. The apparatus of claim 10, wherein working fluid discharged from theutility path is influenced by working fluid discharged from the firstpath of the third stream bypass passage.
 19. A method comprising:operating a gas turbine engine having a core flow path, a fan bypasspath, and a third stream bypass path to convey working fluid through thethird stream bypass path the working fluid conveyed through the thirdstream bypass path originating from the fan bypass path; uponencountering a splitter, branching working fluid from the third streambypass path to form a flow of working fluid in a branch path; andtransferring an energy between the flow of working fluid through thebranch path and a heat exchanger disposed in communication with thebranch path.
 20. The method of claim 19, which further includes changinga flow area of at least one of the third stream bypass path and thebranch path as a result of a change in operating condition of the gasturbine engine, the changing in response to maintaining a flow rate ofworking fluid through the branch path that is adequate for thetransferring.
 21. The method of claim 19, which further includesdischarging working fluid from the third stream bypass path and workingfluid in the branch path to an external location in a manner in whichthe discharging mutually influences each of the working fluid in thethird stream bypass path and the branch path.
 22. The method of claim19, wherein working fluid exiting the third stream bypass path and thebranch path are through independent exits.
 23. The method of claim 19,which further includes flowing working fluid through a fixed downstreamend of at least one of the third stream bypass path and the branch path.24. The method of claim 23, wherein the flowing is through a fixeddownstream end of both the third stream bypass path and the branch path.